Question

the mean of the following distribution is 53 find the missing frequency class 0-20,20-40,40-60,60-80,80-100 frequency 12,15,32,?,13 find the missing one ​

Answer 1

first we have to find the class marks then multiply the frequency with the class marks then the value we get we have to just substute it...hope it helps

Answer 2

The missing frequency is 28.

Value of P= 28.

Given:

Class 0-20,20-40,40-60,60-80,80-100

Frequency 12,15,32,P,13

To find: Find the missing frequency P.

Solution:

We know mean of grouped data is given by

$\bf \overline x=\frac{\Sigma x_i f_i }{\Sigma f}$

here,

xi: Class mark of each class.

fi: Frequency of each class

Step 1:

Create table

$\begin{tabular}{|c|c|c|c|}\cline{1-4}Class&Freq&x_i&x_if_i\\\cline{1-4}0-20&12&10&120\\\cline{1-4}20-40&15&30&450\\\cline{1-4}40-60&32&50&1600\\\cline{1-4}60-80&P&70&70P\\\cline{1-4}80-100&13&90&1170\\\cline{1-4}Total&72+P&&3340+70P\\\cline{1-4}\end{tabular}$

Step 2:

Apply the values in formula of mean.

$53 = \frac{3340 + 70P}{72 + P}$

or

$53(72 + P) = 3340 + 70P$

or

$3816 + 53P = 3340 + 70P$

or

$70P - 53P = 3816 - 3340$

or

$17P = 476$

or

$\bf P = 28$

The value of missing frequency is 28.

Learn more:

1) find the missing frequencies f1 and f2 if the mean of 50 observations is 38.2

ci f

0-10 4

10-20 4

20-30 f1

30-40 10...

https://brainly.in/question/7896418

2) Find the missing frequencies in the following frequency distribution if the mean is 50.25 and the total number of studen...

https://brainly.in/question/7474445